To secure earth embankments against sliding and slumping, the retaining wall industry knows various interlocking and mortarless systems.
Interlock mechanisms which involve pins and sockets, require close supervision by the labourers and the omission of even one pin may compromise the structural integrity of a course of blocks and thereby the entire wall. Also, these pin and sockets mechanisms do not permit significant lateral movement of blocks for working around curves in the embankment.
For large embankments (such as those found near highways), the blocks must be large. Known blocks are solid (i.e. no through core), typically measure in the order of 5′×2½′×2½′ and weigh in the order of 5000 lbs. They are interlocked by large right-angled lugs and corresponding sockets, which severely restricts the ability to create non-90° concave or convex curve wall portions in response to the embankment profile.
For the purposes of this invention, the following definitions will be employed. “Batter” is the apparent inclination, from vertical, of the wall face. A “half-bond” is the relationship or pattern created by stacking units so that the vertical joints are offset one half unit from the course below. For orientation, “convex”, “concave”, “left”, “right” are determined from the point of view of a viewer facing the front face of the block or wall portion. “Lateral” means along the longitudinal axis of the block or course of blocks, parallel to the front face. “Filler” is free draining granular material like crushed, angular rock pieces of perhaps ½″ or ¾″ size.